How to make climate-neutral aviation fly

The European aviation sector must substantially reduce climate impacts to reach net-zero goals. This reduction, however, must not be limited to flight CO2 emissions since such a narrow focus leaves up to 80% of climate impacts unaccounted for. Based on rigorous life-cycle assessment and a time-dependent quantification of non-CO2 climate impacts, here we show that, from a technological standpoint, using electricity-based synthetic jet fuels and compensating climate impacts via direct air carbon capture and storage (DACCS) can enable climate-neutral aviation. However, with a continuous increase in air traffic, synthetic jet fuel produced with electricity from renewables would exert excessive pressure on economic and natural resources. Alternatively, compensating climate impacts of fossil jet fuel via DACCS would require massive CO2 storage volumes and prolong dependence on fossil fuels. Here, we demonstrate that a European climate-neutral aviation will fly if air traffic is reduced to limit the scale of the climate impacts to mitigate.


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This study emphasizes the need for substantial reductions in climate impacts from the European aviation sector to achieve net-zero goals. It argues that focusing solely on flight CO2 emissions leaves a significant portion of climate impacts unaccounted for, up to 80%. The study employs life-cycle assessment and quantifies non-CO2 climate impacts over time. From a technological perspective, it suggests that climate-neutral aviation could be achieved through the use of electricity-based synthetic jet fuels and compensating for climate impacts via direct air carbon capture and storage (DACCS). However, it cautions that increasing air traffic coupled with synthetic jet fuel production from renewables would strain economic and natural resources. Alternatively, compensating for the climate impacts of fossil jet fuel through DACCS would require large-scale CO2 storage and maintain reliance on fossil fuels. Therefore, the study concludes that achieving European climate-neutral aviation is contingent upon reducing air traffic to mitigate the scale of climate impacts effectively.
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